I have a stock '04 SVT ~87K. I'm wondering whether to replace the spark plugs and wires, or go to the dealer to find out if the existing ones are working OK and only replace if he says they're not performing.
8.2mm Taylor Thundervolts and copper core Motorcraft plugs. Hell I did that at 60k on my standard Zetec. I don't care what recommendations are, I don't think I would ever go past 50 - 60k on factory plugs or wires.
And if you take it to the dealer, no matter what any diagnostic will say, I'll be you dollars to donuts that they'll tell you to replace. And charge an arm and a leg.